<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Pdf
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Element.php 18993 2009-11-15 17:09:16Z alexander $
 */


/**
 * PDF file element implementation
 *
 * @package    Zend_Pdf
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
abstract class Zend_Pdf_Element
{
	const TYPE_BOOL        = 1;
	const TYPE_NUMERIC     = 2;
	const TYPE_STRING      = 3;
	const TYPE_NAME        = 4;
	const TYPE_ARRAY       = 5;
	const TYPE_DICTIONARY  = 6;
	const TYPE_STREAM      = 7;
	const TYPE_NULL        = 11;

	/**
	 * Reference to the top level indirect object, which contains this element.
	 *
	 * @var Zend_Pdf_Element_Object
	 */
	private $_parentObject = null;

	/**
	 * Return type of the element.
	 * See ZPdfPDFConst for possible values
	 *
	 * @return integer
	 */
	abstract public function getType();

	/**
	 * Convert element to a string, which can be directly
	 * written to a PDF file.
	 *
	 * $factory parameter defines operation context.
	 *
	 * @param Zend_Pdf_Factory $factory
	 * @return string
	 */
	abstract public function toString($factory = null);


	/**
	 * Set top level parent indirect object.
	 *
	 * @param Zend_Pdf_Element_Object $parent
	 */
	public function setParentObject(Zend_Pdf_Element_Object $parent)
	{
		$this->_parentObject = $parent;
	}


	/**
	 * Get top level parent indirect object.
	 *
	 * @return Zend_Pdf_Element_Object
	 */
	public function getParentObject()
	{
		return $this->_parentObject;
	}


	/**
	 * Mark object as modified, to include it into new PDF file segment.
	 *
	 * We don't automate this action to keep control on PDF update process.
	 * All new objects are treated as "modified" automatically.
	 */
	public function touch()
	{
		if ($this->_parentObject !== null) {
			$this->_parentObject->touch();
		}
	}

	/**
	 * Clean up resources, used by object
	 */
	public function cleanUp()
	{
		// Do nothing
	}

	/**
	 * Convert PDF element to PHP type.
	 *
	 * @return mixed
	 */
	public function toPhp()
	{
		return $this->value;
	}

	/**
	 * Convert PHP value into PDF element.
	 *
	 * @param mixed $input
	 * @return Zend_Pdf_Element
	 */
	public static function phpToPdf($input)
	{
		if (is_numeric($input)) {
			require_once 'Zend/Pdf/Element/Numeric.php';
			return new Zend_Pdf_Element_Numeric($input);
		} else if (is_bool($input)) {
			require_once 'Zend/Pdf/Element/Boolean.php';
			return new Zend_Pdf_Element_Boolean($input);
		} else if (is_array($input)) {
			$pdfElementsArray = array();
			$isDictionary = false;

			foreach ($input as $key => $value) {
				if (is_string($key)) {
					$isDictionary = true;
				}
				$pdfElementsArray[$key] = Zend_Pdf_Element::phpToPdf($value);
			}

			if ($isDictionary) {
				require_once 'Zend/Pdf/Element/Dictionary.php';
				return new Zend_Pdf_Element_Dictionary($pdfElementsArray);
			} else {
				require_once 'Zend/Pdf/Element/Array.php';
				return new Zend_Pdf_Element_Array($pdfElementsArray);
			}
		} else {
			require_once 'Zend/Pdf/Element/String.php';
			return new Zend_Pdf_Element_String((string)$input);
		}
	}
}
